title: Performance of Hereford and two-breed rotational crosses of Hereford with Angus and Simmental cattle: I. Calf production through weaning.
abstract: Cow size, reproductive traits and calf performance through weaning were evaluated in a range environment for Simmental (S) x Hereford (H) and Angus (A) x H crosses in two-breed rotations and straightbred H. Data were grouped into seven dam breed categories: straightbred Hereford (H), crossbred F1 S x H cows (SH), S x H cows of low percentage H (SHS), S x H cows of high percentage H (HSH), F1 A x H cows (AH), A x H cows of low percentage H (AHA) and A x H cows of high percentage H (HAH). Straightbred H, SH, AH, SHS and AHA cows were mated to H bulls, HSH cows were mated to S bulls and HAH cows were mated to A bulls. Cows in the SHS and AHA groups ranged from 1/4 to 3/8 H and their calves from 5/8 to 11/16 H. Cows within the HSH and HAH groups ranged from 5/8 to 3/4 H and their calves from 5/16 to 3/8 H. Cow age ranged from 3 to 10 yr. Simmental-cross cows were heavier and taller and produced heavier calves at birth and weaning than A-cross. Pregnancy rate, calf birth date and percentage of difficult births did not vary significantly among dam breed groups. Within the A x H and S x H rotations, dam breed group rankings for calf birth weight were inverse to rankings for proportion of H in the breed makeup of the calf.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: South Dakota State University, Brookings 57007.
authors.forename: D M
authors.initials: DM
authors.lastname: Marshall
authors.forename: M D
authors.initials: MD
authors.lastname: Monfore
authors.forename: C A
authors.initials: CA
authors.lastname: Dinkel
mesh_terms: D000818:Animals; D001724:Birth Weight; D001835:Body Weight; D001947:Breeding; D002417:Cattle / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development*; D002418:Cattle Diseases / Q000235:genetics; D003433:Crosses, Genetic; D004420:Dystocia / Q000235:genetics / Q000662:veterinary; D005260:Female; D016018:Least-Squares Analysis; D008297:Male; D011247:Pregnancy; D012098:Reproduction; D014886:Weaning; D015430:Weight Gain